Greg Abbott, attorney general and governor-elect, challenged President Barack Obama’s immigration order on Wednesday, saying he stepped out of his bounds.

Abbott issued a statement on Wednesday after filing a lawsuit with 17 other states – including the states of Texas, Alabama, and Wisconsin – claiming that the president’s executive order violated the Constitution’s Take Care Clause, which mandates the president “take Care that the Laws be faithfully executed.”

“The Constitution's Take Care Clause limits the President's power and ensures that he will faithfully execute Congress's laws – not rewrite them under the guise of ‘prosecutorial discretion,’” Abbott said in his statement. “The Department of Homeland Security's directive was issued without following the Administrative Procedure Act's rulemaking guidelines and is nothing but an unlawfully adopted legislative rule: an executive decree that requires federal agencies to award legal benefits to individuals whose conduct contradicts the priorities of Congress."

Abbott spoke about his lawsuit at a press conference on Wednesday after filing it with the United States District Court for the Southern District of Texas. He said Obama’s order differed from those of President Ronald Reagan and President George W. Bush.

“There was never any legal action that determined the legal validity of what President Bush and President Reagan did,” Abbott said. “But most importantly was what President Bush and President Reagan did; [it] was an effort to fulfill legislation that was passed by Congress. In this instance, President Obama has said he is taking this action because Congress will not act. His own words show he is violating the Take Care Clause. He is trying to enact laws himself because Congress will not act. He does not have that authority.”

The lawsuit clarifies that the issue is not with immigration, but about the “rule of the law.” Abbott repeated this on Wednesday, calling Obama and the Department of Security and other agencies’ subsequent orders unconstitutional and illegal.

“Texas and other states that have joined with us are asking for declarative judgment and conjunctive relief,” Abbott said. “We are asking the president to go through the prescribed constitutional process rather than making them up himself.”

The defendants of the case have already acknowledged the 2012 Deferred Action for Childhood Arrivals program and federal government’s failure in enforcing the laws, as well as the consequence of Obama’s executive order, Abbott said.

“As the defendants have acknowledged themselves, Texas will suffer as a consequence of this most recent presidential order,” Abbott said.

Texas and the other states that joined the lawsuit have a strong case, Abbott said. He referenced the Supreme Court case of Massachusetts v. Environmental Protection Agency, and said the outcome of that case proved Texas’s valid suit.

“If you look at the Supreme Court decision of Massachusetts v. the EPA, the Supreme Court granted standing to Massachusetts,” Abbott said. “A doctrine called parens patriae [said] under damages that the people of Massachusetts may suffer from global warming. I will submit to you that the standing of Texas is far stronger than what the Supreme Court granted to Massachusetts in that case.”